Explanation:

- Chandragupta Maurya:

- He is the Mauryan emperor who entered into a marriage alliance with Seleucus Nikator, the Greek ruler of West Asia.

- This alliance followed a military conflict and a subsequent treaty.

- Ashoka:

- He was a later Mauryan emperor known for his role in spreading Buddhism.

- There is no record of him marrying into a Greek alliance.

- Bindusara:

- Son of Chandragupta and father of Ashoka.

- He continued diplomatic relations but did not enter a marriage alliance with the Greeks.

- Dasaratha:

- Grandson of Ashoka and a relatively lesser-known Mauryan emperor.

- Not associated with any notable Greek alliances.